Wellbore Genius

Downhole Simulator

Performance modeling

v1.0Solver: OK

RTA — Blasingame & Agarwal-Gardner

Material-balance time, normalized rate, BDF diagnostics, and late-time PI/HCPV fit.

Transient flow — BDF not yet reached

Late-time slope: -0.674 (target ≈ −1.000 ± 0.1)

Late-window start: i = 81 @ t_mb = 1839.3 d (28/109 pts in fit window)

Fit R²: 0.998 (strong)

Late-time window summary

Window start

i = 81

t_days = 820.00 d

t_mb = 1839.31 d

Points in fit

28 / 109

(26% of series)

log-log slope (BDF)

-0.674

target ≈ −1.000 ± 0.1

Semi-log fit (Agarwal-Gardner)

slope = -0.0003 d⁻¹

intercept = -2.081

⇒ PI = exp(intercept), HCPV = −PI / slope

Samples [-]

109

lateStartIdx = 81

Late-time slope [log/log]

-0.67

Transient

PI [stb/d/psi]

0.1248

R² = 0.998

HCPV [stb]

414

Sample input

Phase

Time

Pressure

Rate

Cumulative

Min late-time points (for fit)

Fit is suppressed when the late-time window has fewer than this many finite (t_mb > 0, qNorm > 0) points. Default 3; range 2–50.

Paste CSV: t, rate, dp [, cum] in the units selected above. Header row optional. Canonical engine units = days · stb/d (or mscf/d) · psi · stb (or mscf).

Upload .csv

Quick-add row (canonical units)

Rate & Δp vs time

log(q/Δp) vs log(t_mb)

min late pts3

Stability if min late pts =

Late-window slope: -0.674 · 28/108 pts

ln(q/Δp) vs t_mb (Agarwal-Gardner)

PI = 0.12478 · HCPV = 414 · R² = 0.998

Rate-integral q_i & derivative q_id

Sample table (109 rows)

i	t [days]	rate	Δp [psi]	t_mb [days]	q/Δp	q_i	q_id	flag
0	10	1111.1	2200	0.0	0.50505	0.50505	3.76880
1	20	1034.5	2200	10.4	0.47022	0.24382	3.47387
2	30	967.7	2200	21.4	0.43988	0.31423	-4.26283
3	40	909.1	2200	33.1	0.41322	0.34231	-3.12455
4	50	857.1	2200	45.4	0.38961	0.35413	-1.97053
5	60	810.8	2200	58.3	0.36855	0.35829	-0.76215
6	70	769.2	2200	71.8	0.34965	0.35841	0.49748
7	80	731.7	2200	85.7	0.33259	0.35624	1.79779
8	90	697.7	2200	100.1	0.31712	0.35276	3.12792
9	100	666.7	2200	115.0	0.30303	0.34849	4.47838
10	110	638.3	2200	130.3	0.29014	0.34377	5.84134
11	120	612.2	2200	146.1	0.27829	0.33881	7.21043
12	130	588.2	2200	162.3	0.26738	0.33373	8.58055
13	140	566.0	2200	178.8	0.25729	0.32863	9.94763
14	150	545.5	2200	195.8	0.24793	0.32357	11.30845
15	160	526.3	2200	213.1	0.23923	0.31857	12.66047
16	170	508.5	2200	230.7	0.23112	0.31366	14.00168
17	180	491.8	2200	248.7	0.22355	0.30887	15.33053
18	190	476.2	2200	267.0	0.21645	0.30419	16.64582
19	200	461.5	2200	285.7	0.20979	0.29963	17.94664
20	210	447.8	2200	304.6	0.20353	0.29521	19.23232
21	220	434.8	2200	323.8	0.19763	0.29091	20.50236
22	230	422.5	2200	343.4	0.19206	0.28673	21.75645
23	240	411.0	2200	363.2	0.18680	0.28268	22.99437
24	250	400.0	2200	383.3	0.18182	0.27874	24.21602
25	260	389.6	2200	403.6	0.17710	0.27492	25.42138
26	270	379.7	2200	424.2	0.17261	0.27122	26.61051
27	280	370.4	2200	445.1	0.16835	0.26762	27.78349
28	290	361.4	2200	466.2	0.16429	0.26413	28.94047
29	300	352.9	2200	487.6	0.16043	0.26073	30.08163
30	310	344.8	2200	509.2	0.15674	0.25744	31.20718
31	320	337.1	2200	531.0	0.15322	0.25424	32.31734
32	330	329.7	2200	553.0	0.14985	0.25112	33.41235
33	340	322.6	2200	575.3	0.14663	0.24810	34.49247
34	350	315.8	2200	597.8	0.14354	0.24515	35.55796
35	360	309.3	2200	620.5	0.14058	0.24229	36.60909
36	370	303.0	2200	643.4	0.13774	0.23950	37.64614
37	380	297.0	2200	666.5	0.13501	0.23679	38.66938
38	390	291.3	2200	689.7	0.13239	0.23415	39.67908
39	400	285.7	2200	713.2	0.12987	0.23157	40.67552
40	410	280.4	2200	736.9	0.12744	0.22906	41.65898
41	420	275.2	2200	760.8	0.12510	0.22661	42.62972
42	430	270.3	2200	784.8	0.12285	0.22423	43.58801
43	440	265.5	2200	809.1	0.12068	0.22190	44.53412
44	450	260.9	2200	833.5	0.11858	0.21963	45.46829
45	460	256.4	2200	858.1	0.11655	0.21741	46.39079
46	470	252.1	2200	882.8	0.11459	0.21524	47.30186
47	480	247.9	2200	907.7	0.11270	0.21312	48.20175
48	490	243.9	2200	932.8	0.11086	0.21106	49.09069
49	500	240.0	2200	958.1	0.10909	0.20903	49.96892
50	510	236.2	2200	983.5	0.10737	0.20706	50.83667
51	520	232.6	2200	1009.0	0.10571	0.20512	51.69414
52	530	229.0	2200	1034.8	0.10409	0.20323	52.54157
53	540	225.6	2200	1060.6	0.10253	0.20138	53.37916
54	550	222.2	2200	1086.7	0.10101	0.19957	54.20712
55	560	219.0	2200	1112.8	0.09954	0.19780	55.02565
56	570	215.8	2200	1139.2	0.09810	0.19606	55.83494
57	580	212.8	2200	1165.6	0.09671	0.19436	56.63519
58	590	209.8	2200	1192.2	0.09536	0.19269	57.42657
59	600	206.9	2200	1219.0	0.09404	0.19106	58.20928
60	610	204.1	2200	1245.9	0.09276	0.18946	58.98347
61	620	201.3	2200	1272.9	0.09152	0.18789	59.74933
62	630	198.7	2200	1300.0	0.09031	0.18635	60.50703
63	640	196.1	2200	1327.3	0.08913	0.18484	61.25671
64	650	193.5	2200	1354.7	0.08798	0.18336	61.99855
65	660	191.1	2200	1382.3	0.08686	0.18191	62.73269
66	670	188.7	2200	1409.9	0.08576	0.18048	63.45929
67	680	186.3	2200	1437.7	0.08470	0.17908	64.17849
68	690	184.0	2200	1465.7	0.08366	0.17770	64.89043
69	700	181.8	2200	1493.7	0.08264	0.17635	65.59525
70	710	179.6	2200	1521.9	0.08165	0.17503	66.29308
71	720	177.5	2200	1550.2	0.08069	0.17372	66.98405
72	730	175.4	2200	1578.6	0.07974	0.17244	67.66830
73	740	173.4	2200	1607.1	0.07882	0.17118	68.34595
74	750	171.4	2200	1635.7	0.07792	0.16995	69.01712
75	760	169.5	2200	1664.5	0.07704	0.16873	69.68192
76	770	167.6	2200	1693.3	0.07618	0.16753	70.34047
77	780	165.7	2200	1722.3	0.07534	0.16636	70.99288
78	790	163.9	2200	1751.4	0.07452	0.16520	71.63927
79	800	162.2	2200	1780.6	0.07371	0.16406	72.27974
80	810	160.4	2200	1809.9	0.07292	0.16294	72.91438
81	820	158.7	2200	1839.3	0.07215	0.16184	73.54332	late
82	830	157.1	2200	1868.8	0.07139	0.16075	74.16663	late
83	840	155.4	2200	1898.4	0.07065	0.15968	74.78443	late
84	850	153.8	2200	1928.2	0.06993	0.15863	75.39679	late
85	860	152.3	2200	1958.0	0.06922	0.15760	76.00383	late
86	870	150.8	2200	1987.9	0.06852	0.15658	76.60561	late
87	880	149.3	2200	2018.0	0.06784	0.15557	77.20224	late
88	890	147.8	2200	2048.1	0.06717	0.15458	77.79380	late
89	900	146.3	2200	2078.3	0.06652	0.15361	78.38036	late
90	910	144.9	2200	2108.6	0.06588	0.15265	78.96202	late
91	920	143.5	2200	2139.1	0.06525	0.15170	79.53885	late
92	930	142.2	2200	2169.6	0.06463	0.15077	80.11092	late
93	940	140.8	2200	2200.2	0.06402	0.14985	80.67833	late
94	950	139.5	2200	2230.9	0.06342	0.14894	81.24113	late
95	960	138.2	2200	2261.7	0.06284	0.14805	81.79940	late
96	970	137.0	2200	2292.6	0.06227	0.14717	82.35321	late
97	980	135.7	2200	2323.6	0.06170	0.14630	82.90263	late
98	990	134.5	2200	2354.6	0.06115	0.14544	83.44774	late
99	1000	133.3	2200	2385.8	0.06061	0.14459	83.98858	late
100	1010	132.2	2200	2417.1	0.06007	0.14376	84.52524	late
101	1020	131.0	2200	2448.4	0.05955	0.14294	85.05777	late
102	1030	129.9	2200	2479.8	0.05903	0.14212	85.58623	late
103	1040	128.8	2200	2511.3	0.05853	0.14132	86.11068	late
104	1050	127.7	2200	2542.9	0.05803	0.14053	86.63119	late
105	1060	126.6	2200	2574.6	0.05754	0.13975	87.14781	late
106	1070	125.5	2200	2606.4	0.05706	0.13898	87.66060	late
107	1080	124.5	2200	2638.2	0.05658	0.13822	88.16962	late
108	1090	123.5	2200	2670.2	0.05612	0.13747	88.82923	late

Decline-Curve Analysis (Arps)

Model:

Imported review:

Kind

hyperbolic

qi [vol/mo]

30333.4

Di [1/yr]

2.000

b [-]

0.80

R²

0.997

MAE

268.65

EUR (50 yr) [vol]

606667

Auto fit comparisonBest by lowest MAE → hyperbolic

Model	qi [vol/mo]	Di [1/yr]	b [-]	R²	MAE ▲	EUR (50 yr)
✓ hyperbolic	30333.4	2.000	0.80	0.997	268.65	606667
harmonic	28929.5	2.000	0.00	0.988	591.07	801078
exponential	24135.0	0.800	0.00	0.919	1377.59	362025

Monthly volume ≈ rate × 30.4 days, averaged per month bin from the loaded RTA samples.

Probabilistic EUR (P10 / P50 / P90)

Per-parameter distribution: pick normal or lognormal, σ as percent (relative) or absolute, and optional min/max clamps. Seeded mulberry32 + Box-Muller. Shaded band is the per-month P10–P90 range; dashed line is the per-month P50.

distributionσ modeσ [log]minmax

distributionσ modeσ [abs]minmax

dMin

distributionσ modeσ [log]minmax

Samples [#]Seed [#]

Multi-well joint history match

shared (b, Di) · per-well qi

Paste pad-level production (one row per well-month). Rows: wellId, monthIndex [#], volume [bbl/mo]. The fitter pools the data: shared decline shape, individual qi.

Model kind

Terminal d_min [1/yr]

3 wells parsed